1. Technical Field
The present disclosure generally relates to storage devices and in particular to using a solid state storage system as a cache for temporary storage of data.
2. Description of the Related Art
As the value and use of information continue to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes, thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
An information handling system can be configured in several different configurations. The information handling system can range from a single, stand-alone computer system to a distributed, multi-device computer system, to a networked computer system with remote or cloud storage systems. The remote or cloud storage systems can include redundant arrays of independent drives (RAID) that use solid state storage devices. Within the computer system or RAID devices are a number of components that include firmware and/or logic and associated storage devices, such as non-volatile random access memory (NVRAM).
While the use of non-volatile random access memory has several advantages such as the long term storage of data without periodic power refreshes, it also has some drawbacks. Non-volatile memory devices have a limited number of write cycles to each cell after which the cell is unusable. Also, each page write may require several write cycles in order to complete the storage of data. While read latency for a non-volatile memory device is approximately on the order of 25 micro-seconds, write latency is much longer at 300 micro-seconds.
Because of the length of the write latency, some solid state storage systems use write buffering/caching to lower latency while improving overall write performance. Since most implementations of write buffering use volatile memory, a method is used to help prevent loss of data during a power failure. The write buffering necessitates the use of extra components such as dynamic random access memories (DRAM) along with a power source such as a battery or large capacity capacitors in order to save the data during a power failure. These extra components increase the cost of the solid state storage system, reduce reliability, and cause inconsistent write performance.